Join Date: Feb 2002
Location: DUB/ORD/SIN/PVG
Programs: EI AerClub Concierge, EK Gold, BA Gold, BD Gold (Retired), HHonors Diamond, Bonvoy Lifetime Gold
Posts: 2,925
In my case (6 legs so far since the switch) it appears to take 14-18 days for the Tier Credits to post and a random number of days for the Avios to appear.
E.g. I now have Tier credits from a flight on Dec 19th but no Avios and neither Avios nor Tier Credits from a flight last week.