Ashaya's last ability and Blood Moon both apply in layer 4. Ashaya changes what Blood Moon applies to, and not the reverse, so Blood Moon depends on Ashaya. That means Ashaya is always applied first. Your nontoken creatures become Forest lands in addition to their other types.

Ashaya is now a Legendary Creature Land — Elemental Forest. Now we apply Blood Moon. Becoming a Mountain takes away Ashaya's land types and abilities but leaves everything else. Ashaya is now a Legendary Creature Land — Elemental Mountain.

Ashaya's power- and toughness-setting CDA would have applied in layer 7a, but now that ability doesn't exist. Ashaya ends up a 0/0 and dies, unless something else is raising its toughness. Once Ashaya is gone, all of that nonsense is undone, and your nontoken creatures...