This does not make sense, why on eatht would anyone want relocatable code in an embedded ROM based system.

the flow must pass to the next page either by SJMP or other relative jump, or by standard program flow.
or LJMP

Using LJMP would cause jump to a fixed, linker determined absolute location.

any absolute jump like LCALL would most probably lead outside the program,
If a ljmp "lead outside the program" you should, I hope, get a linker error

while ACALL would be useful for local ones.
ACALL will still screw up if the linker does not place the entire routine on the same page.

In short, The '51 and other ROM based embedded processors were never intended for relocatable code, trying to make such is "wrestling the architecture into something another procesor would be better at"

I am at a total loss as to why anyone want to make the '51 behave as an x86, If that is what you want, by Jove, use an x86.

Erik