Originally Posted by twilightdream

Whale map will open again on 25/7.
Nothing to rush for it, accessory will stay in shop forever.
But new accessory will be add in future.

By the way I got 1180 from only run all map once.
It's still not worth to waste time for early whale mission in my opinion.

That's because you also got the bonus items from clearing the whale maps first times, which gives some quest rewards. Whale map 1_5 gives only 200 medals, so you'll have to run that one 30 more times to reach 7,000.