I went to cancel my membership which is due to expire in about 9 months time.
but was offered a $30 eBay Gift Card to stay on the plan.
Promotional offers
"Thank You for Choosing eBay Plus - $30 eBay Gift Card"
Note:
This could be targeted offer depending on your membership length, history etc
YMMV
So do you now have to stay on it until after you pay the membership fee for next year, or can you still just cancel in a few month's time?