Yes, a lot of colubrids can and will double-clutch if all the right conditions are met - Brooksi & Eastern (kings) included.
As a matter-of-fact, my largest breeding pair of Eastern Kings did so for me last year (my male is over 6 foot, my female is a little over 5 foot). The female laid 12 huge eggs at the end of May last year, and then 8 more in early August.
If you want your female to double clutch, all you have to do is three things 1. make sure she's always well fed, hydrated and happy, (but not obese).
2. Right after she has finished laying all her eggs offer her as much food as she will take - preferrably all small meals (instead of adult mice, offer lots of fuzzies) since she will be exhausted after laying all those eggs. 3. As soon as she has finished eating, place the male in there with her and they may mate again within a day or two provided you have kept the female happy and well fed all year!
This has worked for me several times even though I did not really plan on double clutching any of them until later in the season...
Here's last year's pics of that pair I mentioned (both were babies from S.GA animals)(female is in bottom photo)
The male actually has some faint brooksi influence aquired in the wild (notice his lighter colors), which is normal in some
S.GA/N.FL animals. (Both of these eat medium rats for me most of the year...)
Zee


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"I am an expert on everything, but I know so little and have so much to learn!" -Carsten "Zee" Zoldy-