Hey ClusterSpouse,
Sorry for the delay in responding... Just got back from a 10-day fishing trip in Alaska...
Great question and thank you for being a super CH supporter. The fastest and most effective way of elevating serum concentrations of vitamin D3 and its first metabolite 25(OH)D is by taking it sublingual (under the tongue) or buccal (inside the cheeks and lower lip). This is where Vitamin D3 sprays and liquid formulations are king as they bypass the GI tract passing directly into the bloodstream through the mucosal membranes in the mouth and this results in better absorption. You can find an excellent study on liquid and spray vitamin D3 at the following link.
https://betteryou.com/health-matters/wp-content/uploads/2016/10/DLux-Cardiff-University-trial.pdf
As the anti-inflammatory regimen is essentially "a way of life" for CHers that's taken daily year round, my only issue with the liquid and spray vitamin D3 formulations is cost. The most effective liquid/spray vitamin D3 are microemulsion preparations that cost considerably more than the liquid gel caps @ 6 cents/5000 IU. I've found that popping/chewing 25,000 to 50,000 IU of vitamin D3 liquid soft gel capsules and swirling the contents under my tongue and between my cheeks and gums without swallowing for 4 to 5 minutes works effectively to get my CH under control during my "25(OH)D burn down" tests to see how long it takes for my CH to return after stopping my vitamin D3 intake.
Hope this helps.
Take care and please keep us posted.
V/R, Batch