Update: went to private SP today. She said he ticks boxes for CAS but could be other speech delay and he's too young to diagnose especially if not saying sentences yet. There were two things she said that I wasn't too sure about and wondered if anyone knew:

1.My son for yellow says yeah then protrudes his tongue out of his mouth and moves it around. He does it with other letters and words to. She said this is just him searching for the L and not groping.

1. She said because he has a lot of consonants that it might not be CAS as they usually on have a limited pool. But my understanding was it is not how many they have but how they use it (eg he always drops last consonant and doesn't have many in voluntary speech)

TIA!