In some areas, number change is required to utilize optic fibre support. Confirm if you have this option available.
If not, then PTCL BB 1-4mbps can work fine depending on your line quality.
My village is on copper lines, but still line quality is ok, so it supports upto 4 mbps perfectly. And on higher speed connections, it has connectivity issues.
Your DSL person will analyze your line perimeters and will let you know in advance that how much mbps connection it can support.
For those relatives having connectivity issues, tell them to downgrade their BB speed 1 step lower (like from 8 to 4, 4 to 2) and their problem will fix.