sorry it took so long to reply. homeport with the seabees depends on whether you are in a NMCB (naval mobile construction battalion), a CBU (construction battalion unit), a ACB (amphibious construction battalion), or any other battalion.
NMCBs are the larger units, and when home, they split off into individual dets...each with a OIC. During your time at home, you will go on one or two field exercises...usually lasting two weeks each where you will "practice" operational readiness for when you are actually deployed. This consists of establishing camp, command operation centers, defensive positions, and what not. You will practice patrols and the logistics of combat. Much time will be spent preparing to receive your SCWS pin (seabee combat warfare specialist). Between field exercises, much time is spent planning projects, weapons training, PTing, maintenance of equipment, practice of the trades (builders, surveyors, steel workers) etc. Aside from the field exercises, you are pretty much in one location the entire time. Some days longer than others, depending on the work that needs to be done.
CBUs are a much smaller version of a NMCB and there is usually one on each navy base. These CBUs do much of the same training, and will build projects on base. The CBU out at Oceana is currently erecting pre-engineered buildings for their training.
All of this varies depending on what unit you are with, where you are located, etc. But this will give you an idea of what is to come with the seabees.
