А можно и без регулярок и parse
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<span>29.03.2018</span><br>
<span>30.03.2018</span><br>
<span>31.03.2018</span><br>
<span>01.04.2018</span><br>
<span>02.04.2018</span><br>
<span>03.04.2018</span><br>
<span>04.04.2018</span><br>
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