Maitenence/Issues in Ashland?

I've seen yellow boards & red boards put up everywhere, at KV cabin, on the Big Sandy sub, from Brown St to Clyffeside, NC cabin, & a mother/slug set (6423 & 2201 I think) have been tied down at the end of the Lex. Ind. Track for the past two days, not moved an inch. Anyone have any idea what all is going on?

Yellow sign with an orange slash is a "Warning Sign" which is advanced warning of a Temporary speed limit or a work area (Rule 89). A Yellow sign is a "Begin Temporary Speed" sign & would mark the beginning of a Temporary speed restriction. A Red sign would be a "Conditional Stop" sign, which a train cannot pass without verbal permission of the employee in charge of the work area per CSXT Rule 89. Perhaps that section of track is being worked on by the track dept and the loco and slug are for a work train assisting in such track work or used to move the track equipment being used.