"Bill" wrote

There is only one duplex outlet(GFCI)on the 20 Amp circuit besides the
garbage disposal. It wouldn't be a big deal to switch out the breaker for
one rated at 15 Amps if necessary.

I would do that anyway. The GFCI is probably only rated at 15 amps, and so
probably the disposal. You don't need a 20 amp, and will better protect the
wire and the disposal.
--
Jim in NC