On the Rics it's the issue that people don't know that on pre-something Rics you have to bend the neck to position and then fix that position via the (loosened before) rods. Just turning the rods won't do it for you. Frequent mistake (and certainly one idiotic system until they changed it). It's not even that difficult to adjust an old Ric, it's just that it is so idiosyncratic to do it that way, you don't know unless you know. And if you don't know, pop goes the fretboard, eventually.
On the Gibbies it's not truss rod related at all, I checked on my RD, loosening or tightening the truss rod had no impact on the loose fretboard.
Really something that shouldn't happen on a bass in this day and age. Doubleplusnotgood.