Absolutely wonderful, historically accurate account of why India has no claims on Gilgit Baltistan and why it was always a separate territory from Jammu and Kashmir. Key points to be noted are as follows... https://thewire.in/diplomacy/how-and-why-gilgit-baltistan-defied-maharaja-hari-singh-and-joined-pakistan

First, GB which included tribal areas and princely states was always under direct British rule through the Gilgit Agency. The Maharaja of Jammu and Kashmir never exercised any right or control over Gilgit Baltistan except for 8 years in the late 1800s.

The Maharaja himself, as we know, was not Kashmiri and was imposed upon Jammu and Kashmir through a sale deed for territories north of Ravi. Muslims, the majority in Kashmir always resented Maharaja’s rule.

GB states of Nagar and Hunza signed separate instruments of accession with Pakistan.

The people of GB revolted against the Maharajah and clearly demonstrated their will to join Pakistan. India’s leadership including VP Menon and others always tacitly accepted this fact.