Look at the history from Pro iPhone and iPads to the non-Pro:
iPhone 15 Pro = A17 Pro
iPhone 15 = A16 (previous year chip)
iPad Pro = M2
iPad Air = M1 (previous year chip)
My guess is since the regular M3 is in the MacBook Pro, they will differentiate Macs similar to the way the regular iPhone and iPads have the last generation chip. This is pretty glaring in the iPad comparison. M2 will be in the Air for some time to come (especially considering 15" just came out in June with the M2 chip). M3 will stay with the MBP. When M4 hits the MBP, then the M3 will transition to the MBA a year from now.
iPhone 15 Pro = A17 Pro
iPhone 15 = A16 (previous year chip)
iPad Pro = M2
iPad Air = M1 (previous year chip)
My guess is since the regular M3 is in the MacBook Pro, they will differentiate Macs similar to the way the regular iPhone and iPads have the last generation chip. This is pretty glaring in the iPad comparison. M2 will be in the Air for some time to come (especially considering 15" just came out in June with the M2 chip). M3 will stay with the MBP. When M4 hits the MBP, then the M3 will transition to the MBA a year from now.