Disney+' has done so well bringing in subscribers in its first seven weeks that two analysts say their projections should be raised. But even with that strong start, the service will need to keep serving up lots more programming to keep audiences from moving on to the next outlet, the analysts warned.

Investor notes released the past two days from Bank of America and Rosenblatt Securities say Disney+ continues to significantly outperform initial expectations. That sent Disney stock up nearly 2.5 percent, to $148.20 per share, in the first day of trading in the new year.

Disney itself has only said how many subscribers it had enrolled by launch day, Nov. 11. That whopping 10 million subscriber figure, boosted by heavy marketing and a string of pre-launch bargains and bundles for early signup, surprised many. But the company has said it won't release new subscriber numbers until its next quarterly earnings announcement, in February.

Other outlets have filled the gap, beginning with a report from Apptopia estimating that 22 million copies of the Disney+ mobile app had been downloaded in the first month after launch.

Analysts are doing their own surveys. Rosenblatt Securities raised subscriber estimates for Disney+ to 25 million through the end of Q1, 2020, based on surveys of video users that showed higher awareness and uptake than predicted. Analyst Bernie McTernan previously estimated Disney+ would attract 21 million subscribers through its first quarter-plus of operations.

Separately, a Bank of America analysis of 29 streaming services found that Disney+'s long-term growth projections – of between 60 million and 90 million subs by 2024 – appeared low.

Despite the strong early start, BofA’s note did sound reasons for caution. Converting early signups into long-term subscribers won’t be simple, particularly as subscribers exhaust the shows they care about most, and big-dollar competitors start marketing their alternatives.

Disney+’s bargains, bundles and Verizon subscriber giveaways undoubtedly helped, BofA noted, as did heavy promotion, and high-profile launch series, especially the breakout Star Wars series The Mandalorian.

But those launch series have now been fully released, and greedily consumed and dissected. Star Wars-loving subscribers who watched them all will need wade through older programming also on the service to find value in their subscriptions.

As far back as October of 2018, Disney CEO Bob Iger had acknowledged one of Disney+'s big challenges: maintaining a high “velocity” of releases of original content that will keep subscribers engaged. In the year and a half since, that challenge hasn’t abated, BofA analysts noted.

“While anecdotal evidence of elevated library consumption on the service is encouraging (both for DIS and the syndication market at large), we cont. to believe more original content will be needed to drive subscriber acq. and retention efforts,” BofA analysts wrote.

Already, stories are popping up online with topics like, “Now that you’re done watching The Mandalorian, consider switching to DC Universe for a while.”

Disney+ fans have access to all the Star Wars movies and existing series, a list that soon will include the just-released blockbuster The Rise of Skywalker. But their Star Wars jones won’t be slaked soon with much new content from that galaxy far, far away, other than through a new season of animated series The Clone Wars. Season 2 of The Mandalorian won’t return until late in the year.

Disney+ clearly is moving to deal with the potential programming lull. This week it also said it is moving up from spring of 2021 to sometime this year the new series WandaVision, built on Elizabeth Olsen’s Wanda Maximoff/Scarlet Witch character. That should help keep Marvel fans, at least, a little more happy.

The company also rolled out a splashy video on New Year’s Day showing “What’s Coming to Disney+ in 2020.” The 61-second video featured about 25 projects, including Season 2 of The Mandalorian, the rebooted Lizzie McQuire, Marvel series The Falcon and The Winter Soldier, several family-oriented series and animated shorts, and previously released features such as 2019’s The Lion King and Toy Story 4, a good bet to win this year’s best animated feature Oscar.

We’ll soon see how important that ongoing content will be. Friends just left its long-time streaming home at Netflix, where its 236 episodes were one of the most-watched blocks of content. Netflix paid $100 million for one year of Friends in 2019.

To fill that and other holes, Netflix has ramped up acquisitions of overseas content, in part to expand viewer options in the United States with “originals” that don’t hail from Hollywood. The international strategy also helps feed its overseas audiences, who have been Netflix’s main driver of growth the past few years.

Friends won’t be available on any streaming service until May, when it helps launch AT&T’s competing HBO Max service. HBO Max is paying $425 million over five years for the Friends rights. Whether endless Friends will be a major attraction for TV audiences by spring, when they’ll have numerous services to choose from, will be a crucial question in HBO Max’s success.