blockchain – Compelled fork of older, low issue blocks

Let’s assume most important chain (A) top is 1000 and the issue adjustment is 50 blocks. At top 450, the issue could be very small. By modifying timestamp of blocks 450-500, I mine a fork (B) such that at top 500 to 600 the chainWork is increased than A on the similar top.

A brand new peer needs to sync with me. I ship B. At top 500 to 600, the peer chooses B and saves A as a fork. Given an extended sufficient pressured forking of A, is it potential for the peer to surrender on A?

If the consumer by no means offers up on a fork, does this open it to fork chain spam assaults?