In some circumstances, primitive short [ă] became [e] in Danian. The two clear examples of this are sc(i)ella < ᴹ√SKAL¹ and spenna < ᴹ√SPAN (Ety/SKAL¹, SPAN). There are also quite a few cases where primitive short [ă] was preserved, such as alm, hrassa and swarn. I don’t know of any similar change in the real-world Germanic languages, so my best guess is that the change [ă] > [e] occurred after an initial cluster of [s] plus a voiceless stop (p, t, k), but this is purely speculative.