Ok. The wording is very confusing. It states, in bold:
Starting on March 9 at 10pm MDNR's first closure of the year for a number of Put & Take trout locations will begin, the first closure period continues until March 29 at 5:30am. The following table will list locations which are currently open to trout fishing and have been stocked
Gwynns Falls is listed. It is also listed in the stocking spreadsheet as being closed until the 29th.
Anyway, I dont begrudge you for fishing. The DNR site isnt very clear, one way or the other.