Fixing seams for a UDIM based texture set?

Hi,

Wondering if there is a tutorial out there about fixing seams in Substance Painter?  This texture set it using UDIM uv's and I need to be able to work across seams to repair the seams that are present.  It's for a human character I created but I used a merchant resource pack as the base and I guess it's got seams that need to be corrected before it can be completed and accepted to the marketplace.  

Honestly, I wasn't planning on another subscription but if I need this program to make the magic happen then so be it.  

Thanks so much
Richard