We did not have advanced math at our base school so we sent our kid to a Math center a few times a week for the entire 3rd grade year.
Kid was not getting what she needed at school so regardless of what happened with the AAP referral, we needed to supplement.
When she entered AAP at 4th grade (for the 5th grade curriculum), she did not have any difficulty at all and scored really well on the SOL.

We moved from a different school system between 3rd and 4th. DD did not have an accelerated curriculum in 3rd, and went into 4th grade AAP.

We did a little online math work the last two weeks of the summer, and she’s done well in math (3s and 4s). Her 3s were from careless errors - she’s solid on all the concepts.

I recommend MobyMax. You set up like you are homeschooling. You can customize so kid is doing math only. There is a 45 minute placement test, and they will say your child has a math level of grade 3.4 or whatever. It will identify gaps (fractions were our weak spot). Then daily work is geared toward eliminating those gaps. FYI, there is a separate math facts section, and you need to go to that one for multiplication and division facts.

The program is free, and it helped with summer slide for DD, who 100% did not want to think about math over the summer.