Employee Notification of Being Bought?

[Bcompliance2003]

Few questions regarding employee benefits during an M&A

1. Does an Employer have to provide advance notice to its employees telling them the company is being sold?

2. The benefits are planning to end on the day of the sale, 10/2/23; when does the seller's benefits end?  Would it be 10/2/23 or 10/31/2023 since their premiums for October are already paid for the month?

3. The plan is to allow the seller's employees enroll into the buyers plan retroactive to the date of the sale (10/2). However, the employees won’t be officially onboarded yet as they will need to go through the full hiring process such as completing payroll docs, I-9s, etc.  Because the seller’s benefits will end on the date of the sale, our client doesn’t want to wait until the onboarding process is complete to offer benefits.  Could this be an issue?

4. If the benefits under the seller don’t end until 10/31/2023, any potential issues if the buyer is the owner of the employees as of 10/2/2023?