Every April I do my annual Lower Water Holes canyoneering trip. We are planning on doing the canyon on March 31st this year, which isn't quite April, but close enough. The core group that I generally do this canyon with is down to two people, so we are opening it up for invites. If anyone is interested, we will have space for 2 - 3 more people. If you're interested, email me at [address removed]. This is done on a permit system, so there is a hard cap on the total amount of people.
If you don't know about Lower Water Holes, it's my favorite Canyoneering trip I have done, however, it's a slighly rugged canyon. You have to switch ropes at an almost hanging belay with 300' of air beneath you for a very long rappel. We finish up by packrafting (Big 5 Pool Boats) four miles on the Colorado River.
With the amount of rappels, terrain to get over, and the float out, this isn't a very good first timers canyon.
Here is some good beta on the canyon: