The top image is the Gemini-6 abort cover. Mission objectives where to rendezvous with the Agena vehicle launched earlier that same day. The mission was scrubbed after the Agena target vehicle exploded during launch. Less than 3,000 where prepared and fewer where canceled on Oct. 25 1965. The reaming covers that where not canceled where held and later released on the rescheduled 15 December launch.
The Gemini-7 mission launched on scheduled to perform its extended mission physiological testing and spacecraft performance evaluation with the added objective to be the target vehicle for the rescheduled Gemini-6 mission. Thus the first dueled manned spacecraft rendezvous.7,380 covers produced.
Two covers where produced for the GT-6 & GT-7 rendezvous mission event.The cachet design was reversed due to printing problems. 11,120 covers of both types produced here,with an unknown breakdown on number of each type to best of my knowledge.