Time dummies in xtabond and xtdpdsys

Hi,

I made three year dummies. One is for 2005-2006, second is for 2007-2013 and third is for 2014-2017. I included only two last variables in xtabond and xtdpdsys models. Is it normal that Stata treats them as D.year07_13 D.year14_17 (this means Instruments for differenced equation)?

Thanks a lot!