Expand shorthand increasing integer sequences
Jelly, 7 bytes

DUṛ"\UḌ


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How it works

DUṛ"\UḌ  Main link. Input: A (list of integers)

D        Convert each integer to a list of its base 10 digits.
 U       Reverse each digit list.
    \    Do a cumulative reduce, applying the dyadic link to the left:
   "       For each pair of corresponding digits:
  ṛ          Select the right one.
           Vectorization leaves digits that do not have a counterpart untouched.
     U   Reverse the resulting digit arrays.
      Ḍ  Convert from base 10 to integer.