According to multiple reports, Twitter is reaching out to some employees to invite them back after a mass layoff last week. Elon Musk, the company’s new owner, laid off 3,700 people — nearly half of its workforce — after completing the takeover.

According to Bloomberg, the company asked some employees to return after they were laid off “by mistake.” It also stated that it was calling back some other employees because they were critical to the development of features for the platform Musk envisions.

Besides this, several posts on the anonymous app Blind suggested that Twitter may have called a few employees back. Casey Newton also reported (via tweet) in a thread on internal slack that the remaining employees were asked to collect a list of potential candidates who might be notified.

People were let go from departments such as human rights, accessibility, machine learning ethics, transparency and accountability, advertising, marketing, communications, engineering, and curation. So it’s not surprising that it realized some of those people could be critical to keeping the platform running smoothly and developing new features.

Musk has promised a slew of new features, including a revamped verification process and an $8 Twitter Blue experience, within weeks of taking over the company. Tesla CEO Elon Musk has also set extremely tight deadlines for these feature rollouts. With so many people laid off across functions, it may be difficult for the remaining employees to complete tasks on time.