Are the WAAS / EGNOS signals valid in the GAGAN coverage area?

The WAAS / EGNOS signals will not give the intended accuracy and integrity in the GAGAN coverage area. This is because the Ionospheric Grid Points (IGP) serviced by WAAS/EGNOS are different from those required for GAGAN coverage area. Also, the GPS satellites visible in the GAGAN coverage will be different from those visible for WAAS/EGNOS. But there will be common area of coverage between the different systems for seamless navigation.