Enumerated multibib bibliography

I have a follow-up question to this one here I posted. In the following example I have split a bibliography using multibib, for which the first bibliography is enumerated:

\RequirePackage{filecontents}
\begin{filecontents*}{\jobname.bib}
@book{Doe2013,
title = {Title I},
author = {Doe, John},
publisher = {Void},
year = {2013}
}
@book{Doe2014,
title = {Title II},
author = {Doe, John},
publisher = {Void},
year = {2014}
}
@book{Doe2015,
title = {Title III},
author = {Doe, John},
publisher = {Void},
year = {2015}
}
\end{filecontents*}

\documentclass{article}
\usepackage{multibib}
\newcites{ll}{Subsection of A}
\usepackage{xcolor}
\usepackage{hyperref}
\hypersetup{
allcolors=cyan
}
\usepackage{etoolbox}
\makeatletter
\patchcmd{\thebibliography}{%
\chapter*{\bibname}\@mkboth{\MakeUppercase\bibname}{\MakeUppercase\bibname}}{%
\section{References}}{}{}
\makeatother
\usepackage[authoryear,sort,round]{natbib}
\renewcommand\refname{Bibliography}

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
\begin{document}
\section{PART A}
A reference to \citell{Doe2013} and \citepll{Doe2014}, and another to \citep{Doe2015}.

\makeatletter\renewcommand{\@biblabel}[1]{#1.}\makeatother%
\renewcommand{\bibsection}{\subsection{\bibname}}
\bibliographystylell{plainnat}
\bibliographyll{BibProb}

\section{PART B}
Same reference to \citell{Doe2013}, but also to \cite{Doe2015}.

\makeatletter\renewcommand{\@biblabel}[1]{\hfill}\makeatother%
\renewcommand{\bibsection}{\section{\bibname}}
\renewcommand{\refname}{Bibliography}
\bibliographystyle{plainnat}
\bibliography{BibProb}
\end{document}


This produces:

I used the following in the first bibliography to enumerate it:

\makeatletter\renewcommand{\@biblabel}[1]{#1.}\makeatother


though the actual numbering sits in the margin. How can I make it flush left and aligned with the section and subsection numbering?

After much searching, there is an alternative with Biblatex and the category notcategory approach of separating bibliographies. In the following solution I also make use of sorting the year in reverse chronological order (option "sorting=ydnts"):

\RequirePackage{filecontents}
\begin{filecontents*}{\jobname.bib}
@book{Doe2013,
title = {Title I},
author = {Doe, John},
publisher = {Void},
year = {2013}
}
@book{Doe2014,
title = {Title II},
author = {Doe, John},
publisher = {Void},
year = {2014}
}
@book{Doe2015,
title = {Title III},
author = {Doe, John},
publisher = {Void},
year = {2015}
}
\end{filecontents*}

\documentclass{article}
\usepackage{xcolor}
\usepackage{hyperref}
\hypersetup{
allcolors=cyan
}
\usepackage{etoolbox}

\usepackage[natbib,style=authoryear,backend=bibtex,sorting=ydnt,defernumbers=true]{biblatex}
\DeclareBibliographyCategory{SubBib}
\defbibenvironment{sub}
{\begin{enumerate}}
{\end{enumerate}}
{\item}

\usepackage{xparse}

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
\begin{document}
\section{PART A}