I've tried to understand why Scotland is so far behind, and read an article in the Spectator which I won't link to as it gives political reasons. However it does say that some of the delay is procedural, so here's that section;
"The issues Scotland is facing could well date back to health policy decisions made before the pandemic. For all their controversy, Andrew Lansley's NHS reforms made during the Coalition years have stood England in good stead for a mass vaccination programme by empowering GPs.
But the situation north of the border is more confusing. Scottish GPs face labyrinthine layers of bureaucracy when it comes to getting hold of vaccines. First, they have to approach their regional health board who passes on the information to NHS Scotland's National Procurement service, which then advises its 'distribution partner', healthcare firm Movianto. According
to Scotland's 'vaccine deployment plan', 'once stock is released for ordering, the distribution partner inputs the GP orders on to their ordering system'. The vaccines are then typically delivered only once a week to GP surgeries. Confused? So am I. With so many hurdles between the GPs and the doses, it’s little wonder the rollout has been so slow."
Not the whole story, but does go some way to explain the slowness.