Will a HR54 work with 3 HR24's ???

Customer had (4) HR24's. 1 went bad and ATT shipped him a replacement over 1 1/2 month ago. Cust. got busy and just called me to come out and help activate and ATT said they cant activate the replacement HR24 after July 1,2021. So they are going to send him a HR54 instead. Obviously that will max out the tuner capacity (5+2+2+2=11) on standard SWM LNB setup but if you set the HR24's to single tuner will that work (5+1+1+1=8)? Also assuming it does work would all of the whole home features still work (record in one room and watch in another, etc...)? If not, I know he could just get 3 clients but everything is already setup now and its just a pain if it wont work that way. Had he only activated a 1 1/2 month sooner :(