We already know the earth wobbles. But do we know if latitudinal and/or longitudinal lines change with the wobble?
No. Zero degrees goes through the “Center of the instrument at Greenwich.” As long as that stays in one place so do the lines.
It would be huge problem for GPS systems, if they did.
Ed
Not quite. The north pole also needs to be fixed to one specific point on the Earth’s surface, or else the Greenwich meridian would start in a different spot.
Thus, to compensate for the Chandler Wobble, apparently a specific North Pole has been defined in order to keep everything from shifting by a few meters over the course of months - the geographic north pole isn’t reliable enough. 
Ok so we compensate for the wobble by fixing a geographic north pole that does shift…on occasion. I wasn’t really talking about the long/lat lines shifting by miles, to really effect GPS systems…but they do shift by meters here and there no?