If you have more than a single source, then apt will already be checking this for you.

The default is more than a single source.

All of mine point to like somethingsomething.ubuntu.com

	▲	shakna 2 days ago \| parent [-]
		If it points to mirror.ubuntu.com, it'll be mirroring at host end, instead of inside apt. But as apt does do resolution to a list, it'll be fetching from multiple places at once.