Yes while coming back from Chandrashila , it rains after 12 pm generally in mountains so you can plan your Yatra early in morning and make sure you get back to base camp by 2 pm
Hi , ok so first time trekkers should be very careful because you can have breathing issue at such high altitude , please carry relevant medicines and Vicks inhaler ye sab aapko high altitude sickness se bacha sakte hai and yes carry one puffer jacket and one fleece jacket , normal T-shirts and lowers as there will be hot in day time and cold in morning and evening
Frankly speaking network condition in Chopta is not good only few spots can give u network otherwise no network at all , you may still try Jio or BSNL they have some networks