Cal deficiency or rust fungus?

grown the strain multiple times never seen this, but each seed is a little different. Start of week 6 flower if that makes a difference.
Never had calcium issues before since I use tap, also the molasses has calcium.
Also been dealing with some gnats but never seen it manifest like this.

thoughts?

Might be calcium deficiency early. Youre in the window for calcium demand. The only time I feed cal mag with no spotting is week 4-5 in bloom. About a month in it’s usually needed.