I ordered Feb. 3, order got accepted May 4, finally I got an email today from GM saying my vehicle is being built. I have a 3.0L LM2 in my truck so I don't know how bad the constraint is. I suggest you don't settle. If you are paying 60 grand for a truck, it better have everything you want. I didn't wanna delete the CarbonPro package so I bit the bullet for 4 months and it's finally paying off. Just an FYI though, usually if the order is accepted, they don't make you change your options, if your order was accepted with the LM2, you shouldn't have to change unless it is on extreme constraint. It usually means they just wont pick up anymore orders with the LM2.