Glad to hear you ordered the test kit. We'll have to wait for the test kit to get started, but there's only a few possibilities. Better experts will chime in wherever I'm wrong.
1. There's an algae bloom underway, and the bleach was consumed neutralizing it.
2. It's less common, but possible you have CYA-eating bacteria, that convert CYA to ammonia. The ammonia will consume the free chlorine very quickly. The puzzle is that CYA is usually zero if this condition exists, but maybe Leslie's result was off (this is the other thing we need the proper kit for)
3. If CYA is zero, and your tests were done in full sun, FC would drop from 4 to 2 in about a half-hour, and then from 2 to 1 in the next half hour, so you should have detected some on the test-strip. It sounds like the test strips are fresh because you did detect FC after adding the bleach.
We've yet to hear what your water looks like. It could be clear under these conditions, but more likely a bit cloudy and whitish, bluish, or green. Could you describe it?
This may not prove helpful, but please pour another gallon in after the sun is off the pool with your pump running and do a test 10 minutes after adding the bleach, and then again 10 minutes after that. If you have lots of strips, another at 30 minutes and/or 1 hour might be helpful. When you get your kit, you won't need the strips anymore.
When you get a chance, please add your pool finish, pump HP, and filter type to your signature. Not relevant yet, but it will be later. Thanks.