New regulatory filings from Dish Network indicate that the company may divest its Boost Mobile assets. Boost is the largest of Dish’s four retail wireless MVNOs, which will be migrated to its own network as that is built out and as subscribers upgrade to 5G (they currently run on AT&T and T-Mobile networks). Dish chair Charlie Ergen, and treasurer Jason Kiser, have set up a special purpose acquisition company (SPAC), currently a popular M&A instrument in the US hi-tech business, called CONX, which would acquire Boost. Some analysts speculated that this was a sign of what skeptics have believed since Dish first invested in 4G spectrum – that Ergen has no real interest in building a long-term mobile operator business,…