Spring is an early bird. Newer before in my + 20 years with bonsai, have I moved trees from their shelter late February and early March. The weather is mild as a Caffé latte, and therefore it is better to acclimatise the trees now, so they are adapted to the weather outside. If it should turn colder with frosts during some days, I will use a good half hour putting the trees back to the green house as long as it is needed. But for now, it is better having the bonsai in open air, rather than a overheated greenhouse. Re-potting will begin soon.