If you want to later convert back to extended distance mode from synchronous mode, follow these steps:
CSUSPEND DEVN(X'F41') PRIM(X'A763' FCA76 X'6B' X'03')
SEC(X'A762' FCA76 X'1E' X'02') PRIMARY
CESTPAIR DEVN(X'F41') PRIM(X'A763' FCA76 X'6B' X'03')
SEC(X'A762' FCA76 X'1E' X'02')
MODE(RESYNC) MSGREQ(NO) OPTION(XD)