Deductions & credits

Yes the program did not add regular depreciation the first year. Just bonus depreciation with limit. 
One question though. When regular depreciation is limited in a given year the basis carries to the next year for a calculation and so on. If any depreciation left after 6 th year then you continue to so why does excess bonus depreciation from the limit not carry to year 2 and instead skip to year seven? I don’t see that explained anywhere in the depreciation instructions from the IRS. Can you point me to this weird rule?