I know some of the replies are joking but I actually did hear there is some substance to the ATR rumor though I haven’t heard of the A220 part.
Apparently AW and RM have taken several trips to France to the HQ.

Reliable source in Dallas says they have no plan to phase out the 135/145 but instead want to support the shorter flights in and out of LAS/SNA/BUR/OAK with the ATRs and keep the ERJ for anything over 400 miles.

I assume United would be footing the bill for the ATRs if I was to bet.