Flights are available daily and have no minimum stay requirement. Travel dates are blacked out around the Christmas and New Year holiday, but other than that this fare is widely available with short layover times in either SEA or MSP, so no backtracking.
As an example, I found seats departing BOS on Friday, September 21 and returning from ANC on Saturday, September 29, 2018.
There's no shortage of good fares out of Beantown today, so make sure to take a look at our Boston (BOS) flight deals page.
Need a room Anchorage? Here's a list of what's available for the sample dates on Hotelwatchdog.