Wednesday, 2 days later - both stocks and warrants are showing. So, a total of 3 business days with no fees. Aside from the 1+ hour wait and having to hunt for the corporate actions page & phone# it was a relatively painless experience.

The following Monday morning (split was submitted on a Friday) my account is showing the shares, but no sign of the warrants yet.

Split units of 3 SPACs in my taxable account, so can report on the retail side's corporate actions team. After a 1 hour hold an agent finally came on line (I gave up after 30 minutes on the two days previous). There was some back-office issue with one of the SPACs, but 19 minutes later all three were submitted. After several more minutes my account history shows journal entries for the split, but so far no sign of the shares or warrants in my positions page - only the pending Unit split. Will update when that changes.