Lightning Network – What is the maximum number of hops an onion message can travel?

Since the header is 66 bytes (version 1, public_key 33, HMAC 32), the payload is 32834 – 66 = 32768 bytes. The OM mid-hop payload is at least 70 bytes (length 1, HMAC 32, type 1, subtype 1, blinded_node_id 33, enclen 2). So the maximum travel distance is 32768/70 = 468 hops. Are these calculations accurate?