Toddler waking too early!

My LB is 2.5 and ever since we took the cot sides off his bed the lovely 12 hour a night sleeping has gone. Back in mid august last year we caught my then (almost 2 year old) climbing his cot sides so we removed them. From that night on our problems started. Apart from the odd period of about 6 weeks we’ve consistently been up at 5:30 - 5:45. And when my little boy is up he is up, there is no gradual waking up, if we are not on top of our game he will be into everything. Currently, he goes to bed at 7:30, if I put him to bed he rolls around like he can’t get comfortable for an hour, if it’s my husband he’s off in about 20 mins. 🙄🙄 we don’t do anything different. I’ve been on bed duty all week due to hubby being on lates, it’s made no difference to the morning wake up time. We do allow a nap in the day when he chooses, but always before 3pm and he sleeps for 1-2hours. We’ve tried everything, I’ve been taking him for walks to the park of an evening, it makes no difference, making bed time later makes no difference. We went swimming yesterday and he was really tired by bed time.. still up at 5:45. My husband works unsociable hours due to being a lorry driver, so he’s usually gone in the mornings and it falls to me to get up even though I too work 8-4 everyday. During the day my LB is a whirlwind, he is constantly on the go, I have to have eyes in the back of my head all the time, (he would climb drawers etc if left to his own devices) so I just don’t understand why he doesn’t need more sleep. I’ve been told about the alarm clocks that change colour when it’s time to get up, but I just don’t think this will work. Currently, when he wakes up I go in his room, but him back in bed and lay on his floor with no interaction, he just reaches over and gets his books, or bangs on his bed etc. I really don’t know what else to do.