I have not been a stamp collector for 20-30 years + I have 3 rows of 4 US Official Mail Scott # 140. They are attached to the portion of the envelope, but have never been cancelled. Is it better to leave them as is, or should I soak. Also I have a grouping of same official stamps on portion of envelope with a$5.00, 4 $1.00, 2 .022. 1 .04, and 3 .01 cent stamps. These have all been cancelled with what looks like a blue highlighter drawn through them. keep as a group or separate?
Thanks for any insight

